12 years separate veteran Alejandro Valverde (Movistar) and Simon Yates (Mitchelton-Scott) but now only 25 seconds cleaves the pair on the Vuelta GC with just three stages remaining before the procession to Madrid.
The Spaniard pulled clear from Yates with Enric Mas (Quick-Step Floors) in the final, brutal throes of Stage 17.
With the help of brother Adam, deployed by Mitchelton-Scott at just the right time this Vuelta, the race leader hung tough, conceding just eight seconds. Earlier with around three kilometres from the top, Aussie Jack Haig reeled in a frisky Valverde.
"Of the stages left, this is the one I feared most," Yates said, not too upset about Valverde closing in.
"There’s still a lot of racing to come, hard stages ahead. I truly believe Andorran stages are much better for me I know Andorra very well and I think the climbs suit me very well."
Although only two minutes and 11 seconds behind Yates, Quintana conceded leadership of Movistar to his elder.
"Alejandro was really strong today, and we will support him," he said. "This team has always worked like that. It’s up to the race itself to dictate on leadership in case of shared roles, and what matters is having a team-mate win.
"We’ll continue to work, just as we’ve done during the whole race.
Valverde was a bit more diplomatic. "We’ll speak in the hotel to see what we can do from now on. Enric (Mas) is third, of course he can win La Vuelta. It’s difficult but he’s going step by step. I’m not so far either.”
In just the second grand tour of his life, youth classification leader Mas rounds out the podium, one minute and 26 seconds in arrears.
"Finishing in the top three would be a dream, but the goal remains the same, to take it day by day," he said. "I had good legs and could cope with the pace of the Yates brothers, who controlled things on Balcon de Bizkaia, and then with Alejandro's kick.
"This only helps my confidence grow as we race towards the finale in Madrid."
Sitting only 14 seconds behind Mas, Miguel Ángel López also showed on Balcón de Bizkaia he isn't done with this Vuelta just yet.
"Today, I just gave my best on the final climb. The team once again did a great job for me and I just tried to stay in front and to gain some seconds over my rivals. It was a very hard day."
Vuelta 2018 Top 5 after Stage 17:
Simon Yates (Mitchelton-Scott)
Alejandro Valverde (Movistar) +25
Enric Mas (Quick-Step Floors) +1:22
Miguel Ángel López (Astana) +1:36
Steven Kruijswijk (LottoNL-Jumbo) 1:48